ThePipingMart Blog Grades Alloy AL 800 (UNS N08800) – Composition, Properties, and Uses

Alloy AL 800 (UNS N08800) – Composition, Properties, and Uses

Alloy AL 800

Alloy AL 800 is a unique nickel-iron-chromium alloy with excellent high-temperature oxidation and carburization resistance. This superalloy has many applications in numerous industrial and engineering sectors due to its superior physical and mechanical characteristics. To better understand Alloy AL 800, this blog post will thoroughly analyze its composition, mechanical and physical properties, corrosion resistance, welding techniques, and typical uses.

Alloy AL 800 Composition

Alloy AL 800 combines 33% nickel, 21% chromium, 45% iron, 0.35% manganese, and 0.15% carbon. The nickel content of Alloy AL 800 prevents corrosion by neutralizing acidic and alkaline environments, while the chromium and iron elements provide excellent resistance to scaling, oxidation, and carburization. Manganese and carbon are added to enhance the alloy’s strength and toughness.

Element Content (%)
Iron, Fe 44.5
Nickel, Ni 32
Chromium, Cr 21
Manganese, Mn 1
Aluminum, Al 0.4
Titanium, Ti 0.4
Silicon, Si 0.35
Copper, Cu 0.3
Carbon, C 0.02
Phosphorous, P 0.02
Sulfur, S 0.01

Alloy AL 800 Mechanical Properties

The mechanical properties of Alloy AL 800 are exceptional, making it an ideal alloy for high-temperature applications. Its ultimate tensile strength (UTS) is 635 MPa, while its yield strength is 295 MPa, enabling it to withstand extreme stress and tension. With its elongation at a break of 45%, the alloy can absorb massive shocks and vibrations without breaking or deforming.

Properties Metric Imperial
Tensile strength (typical annealed at 982°C/1800°F) 600 MPa 87000 psi
Yield strength (typical annealed at 982°C/1800°F, at strain 0.200%) 295 MPa 42800 psi
Elongation at break (typical annealed at 982°C/1800°F, in 2″) 44% 44%
Hardness, Rockwell B (typical annealed) 70 70

Alloy AL 800 Physical Properties

Alloy AL 800 has excellent physical properties, including a high density of 7.94 g/cm³, a high melting point of 1430℃, and a low thermal expansion coefficient. Its thermal conductivity of 12.5 W/mK makes Alloy AL 800 an ideal material in heat exchangers, furnace components, and piping systems.

Properties Metric Imperial
Density 8.08 g/cm³ 0.292 lb/in³
Melting point 1371°C 2500°F

Alloy AL 800 Equivalent

AMS 5766 AMS 5871 ASTM B163 ASTM B366
DIN 1.4876 ASTM B407 ASTM B564

Alloy AL 800 Corrosion Resistance

Corrosion resistance is a crucial factor when selecting an alloy, and Alloy AL 800 has excellent corrosion resistance properties. It can resist severe corrosion caused by acidic and alkaline solutions, especially under high-temperature applications. It also has anti-scaling and anti-carburizing qualities, making it useful in hostile environments.

Alloy AL 800 Welding Techniques

Welding is critical to Alloy AL 800’s application, and several welding techniques can be applied. Shielded metal arc welding (SMAW), gas tungsten arc welding (GTAW), and plasma arc welding (PAW) are the most effective welding processes used to join Alloy AL 800.

Alloy AL 800 Applications

Alloy AL 800 has numerous applications in different industrial and engineering sectors. It is extensively used in aerospace, furnace and heat exchanger components, oil and gas industries, chemical production facilities, power generation plants, automotive exhaust systems, and thermal processing equipment.


Alloy AL 800 is an essential nickel-iron-chromium alloy with excellent mechanical and physical properties, superior resistance to high-temperature oxidation and carburization, and outstanding corrosion resistance. Its unique composition makes it useful in different industrial and engineering applications, ranging from aerospace, oil and gas, chemical production, power generation, automotive, and thermal processing equipment. By understanding its composition, mechanical and physical properties, corrosion resistance, welding techniques, and common uses, one can appreciate the critical role Alloy AL 800 plays in various sectors.

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